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Use parentheses as appropriate for explanatory material in text and as shown in the examples that follow.

1. Parentheses in Equations

In equations, use parentheses, brackets, and braces in this sequence (which may be repeated as needed).

{[( )]}

2. Parentheses with Measurements

Use parentheses around English measurements that follow SI (metric) measurements.

3.1 m/s (7 mph)

3. Parentheses in Citations

When you use parentheses in text, such as for author-date references or for parenthetical (added) information, place a comma after the parentheses rather than before them.

In earlier research (Jones 1989), we showed how quantities of lipids could be increased by this method.

4. Nested Parentheses in Text

In body copy, use parentheses, brackets, and braces in this sequence, which may be repeated as needed: ([{ }]).

(The data presented here [originally derived from Mason {1998}] should not be used for location-specific analyses.)